SA99200023B1 - The hydration method of olefin - Google Patents

Abstract

Abstract: This invention relates to a continuous method for the hydration of olefins with water in a vapor phase to the corresponding alcohol in the presence of a multiple mixed acid salt as a catalyst. Polymixed acid is a mineral salt of silicotung acid or phosphotungstic acid soluble in a polar solvent at less than 40 °C, wherein the metal in the salt is an alkali metal or an alkaline earth salt.

Description

Y _— _ hydration method (43,4) olefin Full description AY - 313 a a This invention relates to a method for the hydration of olefins to alcohols alcohols using a mixed mixed acid salt as a catalyst The process of hydrating olefins such as ethylene or propylene to the corresponding alcohols by hydrating them in a vapor phase using a precipitated phosphoric acid catalyst A well-known process is performed on a silicone support. There are many previous publications demonstrating this process, including those set forth in Patent 1-174 BR 808505845 - BR 1-719059 A TE PAY 017457 BR 97565946 BR 97565946 1-A; British CATV EY 0 and American 445774”-A Canadian mA Ef A. In each of these publications, the nature of the siliceous support siliceous is limited by several variable criteria including bore size; surface area ¢ And the crushing intensity ¢ and the purity of the support Some of the previous publications Jie bel British 1 110 show a liquid phase method for hydration saa) olefins 15 using a catalyst of mixed acid; as well as; ve states US Pat. No. 1771/97-7a a method for the vapor-phase hydration of olefin 8 to the corresponding alcohols using a polymethylated acid as a catalyst; It includes an anion complexed with one element of group VI; Subset A of the AREA table

creamy

league. It is mentioned in this reference that a catalyst can be used with or without a support. It is said that the supports, when used, are preferred to be silica gel, although it is possible to mention other silicone supports, Jie, silicic acid, the Japanese acid child; bentonite; asbestos; likewise; The Japanese patent f—oviv.aro describes a method for the hydration of olefin 2 using a polybleached acid catalyst as a support on activated carbon. The US patent also states; 02867+0?-a polybleached acid supported on a predominant amount of metal oxide Inorganic metal oxide Hydroxide An inorganic metal hydroxide as a catalyst for a number of general organic reactions including Lab, including the hydration of olefin. Among the pillars shown in this patent, we find alumina “magnesia alumina” thoria

“titania” and the like, preferably alumina. One of the problems of using mixed mixed acids as catalysts for the hydration of Jie olefins ethylene and propylene to the corresponding alcohols is limited to the fact that the catalysts are highly effective and the reactions tend to be exothermic 1 To the highest extent, which causes the operation and work procedure of the device to be dangerous on a commercial scale. Furthermore ; We find that the use of mixed and multiple catalysts shows good performance when used in a one-pass reaction. But the conversion of ethylene by one-pass method is usually only about 77. And on that; find in operating on a commercial scale; that it is necessary to re-pass the olefin back into the hydration reactor 0 in order to maximize the utilization of the olefin charge; Also, the presence of traces of impurities such as aldehydes, ethers, some alcohols

And some dimers / polymers of olefin in that recycled olefin tend to inactivate or completely decompose the catalyst; moreover, we find that with the recommendation of some salts of mixed acids We do not find among the salts used (Sele 0) to say that they are soluble under ambient conditions in readily available solvents, in most cases due to the high concentrations of 5 cations present in Salt as = 1 mole of potassium per mole of mixed acid, those that adversely affect its solubility.Moreover, we do not find any of those salts used in a continuous method al hydration of olefin that It includes the return of the unreacted olefin to 0 hydration reaction Thus, we see that there is no description yet of a specific polyhydric acid salt as a catalyst in a certain continuous method of hydration of olefins to alcohols Corresponding alcohols that get rid of the previous problems. It has now been found that the method can be improved by using certain salts of various mixed acids as a catalyst that controls the activity as well as calculating it by using certain conditions 1 of the method. A general description of the invention based on the foregoing; This invention is considered the first continuous hydration method. Fenate with water in a vapor phase to the corresponding alcohol (alcohol) in the presence of a mixed poly-acid salt as a catalyst. The mentioned method includes re-circulating the unreacted olefin to the reaction of 0 hydration characterized by the fact that the mixed poly-acid salt is a silico acid salt Producestick Ed

Silicotungstic acid or phosphotungstic acid soluble in a polar solvent at an OF of 560 °C where the metal in the salt is an alkali metal or an alkaline earth metal. The phrase “heteropolyacids” used in this description means to denote silicotungstic acid and phosphotungstic acid with or without any water to crystallize. The phrase 'polar solvent' within this description is also intended to denote one or more water or lower aliphatic alcohols (such as alcohols with -1 carbon atoms) or glycohols (It has from ? to 5 carbon atoms) and ketones (Ji) acetone or methyl ethyl ketone ve. It is appropriate that the catalyst has more than four grams of an alkali metal cation an alkali metal cation © or two moles (ml) of an alkaline earth metal cation per gram mole of the poly-mixed acid, and it is desirable that one to two mono-valent cations be present in the salt of the poly-acid and therefore it is desirable that It is a mono- or di-potassium salt. It is appropriate for the catalyst to be supported on 1 siliceous support, and the supported catalyst is denoted later as “Ac gens” catalyst. Silica gel or synthetic silicates 15 prepared Sie from fumed silicas or flame hydrolysis of silicon tetrachloride. The support can be in any suitable physical form such as granules, pellets or extracts. Note that these grades are available as outputs from Ye Grace (OV type or grade) and Degussa (Yo Degussa) respectively. And from AREA

It is appropriate to prepare the supported catalyst (the catalyst group) by impregnating the support with two salt solutions of the mixed acid mixed in a cycle by dissolving the salt of the mixed acid such as alcohol, alcohol or distilled water. Then the support is added to the solution formed. It is appropriate to leave the support to soak in the mixed acid solution for a period of several hours, with periodic manual stirring; After this time, it is filtered in an appropriate manner using a Buchner funnel in order to increase any acid salt. Lad can use other impregnation techniques such as the primary wet process. Then the suitably formed wet catalyst is placed in an oven at a high temperature for several hours when dry; After that time it is allowed to cool to ambient temperature in a desiccator. And we obtained the weight of the catalyst on drying; And the weight of the used support and the weight of the acid on the 0 support by subtracting the last weight from the weight, JN, and from it the charge of the catalyst is determined in grams / liter. Then this catalyst group (measured by weight) was used in the olefin hydration process. The degree of hydration of the mixed polyacid can affect the acidity of the catalyst and thus its activity. Consciousness Any or all of the effects of the olefin hydration sss process can alter its hydration and oxidation of the metals in the mixed polyacid 1 salts; That is, the actual catalysts under process conditions may not retain hydration/oxidation states of the metals in the multiple mixed acid salts used to impregnate the support. It is normal; then; Predict that the states of sad hydration and oxidation could be different in the catalysts used up after the reaction. Lad can modify the catalyst supported by a multi-mixed acid (the catalyst group) by adding phosphoric acid or any other mineral acids to it. Mr. Dr

VY — _ It is appropriate to perform the process using the following reaction conditions:

A- It is desirable that the molar ratio of water to olefin passing through the reactor range from

CN - 1 (preferably Tee)

b- The velocity del dl per hour for the gas (GHSV) of the water/olefin mixture is appropriate from ve Yo to yo and 0 g/min/cm of the catalyst group.

,. From the catalytic group Yan g/min/1.01 to 07

C- The catalyst concentration of the mixed acid ranges from © to 7560 and/or based on weight

total from the catalytic group; 770-01 w/w of the total weight of the set is recommended

Catalytic.

1 The process of hydration of olefin takes place at a temperature of 150-780 C. During this rate of temperature, it is desirable to hydrate ethylene to ethanol at a temperature ranging from the dew point to Vor m; It is estimated from You to 706 m; It is appropriate for the hydration of propylene to isopropylene at a temperature ranging from the dew point to 501°C.

,. . Yo. —Yo. yo

It is appropriate that the olefins to be rehydrated are ethylene

The propylene and the corresponding alcohols formed should be ethanol.

olefins respectively. These olefins can be used as isopropanol and isopropanol ethanol

pure or mixture of olefins to generate the corresponding mixture of alcohols. As for

M - Feed shipments of mixed hydrocarbons issued, for example, from a refining unit. From a fluid catalytic cracking process that includes saturated and unsaturated hydrocarbons in it? to SLY carbon it can be used for this purpose. The process takes place in a vapor phase, meaning that both olefin and water are in a vapor phase above the catalyst group. Notwithstanding 0 the small percentage of each gaseous reactant dissolved in the catalyst group . It is believed that the reaction of hydration occurs between these melt reactors. The olefin symmetry ethers are formed as by-products during the reaction. The method is also improved and optimized by recycling all olefin reactants; if i want to; After removing unwanted impurities, Leia; back to the reactor.

01 The hydration all process is carried out by placing the catalyst group in Jolin and closing it tightly, then heating the catalytic group to the reaction temperature. And heating the catalytic group to a temperature of 150 to 200 C, stopping this required final product. For example, if the final product is ethanol - from ethylene, then it is appropriate to heat the catalyst group from 001 to 800, preferably from 7001 to 7760, and the best is from -701 145 C. On the other hand; if

ve the end product was isopropanol from propylene ; It is appropriate to heat the catalytic group to a temperature ranging from slightly above the dew point to Ca VAS, and when the catalytic group reaches the required temperature, a charge of olefin and water in vapor state passes through the reactor. It is appropriate that the molar ratio of the water to the olefin passing through the reaction ranges from 1.1 to 3.0; Preferably from 1.1 to 01

olefin to 48 ; Also, the space velocity of the water vapor/olefin mixture is 1.75 and better than the Ys olefin water through the reactor is subject to slight variations depending on whether the olefin is

The reactant is ethylene or propylene. for example; in alls the two are ethylene; It is appropriate that the spatial velocity of the mixture of it with water vapor is from 000 to CVn, preferably from ve 0 to On 4 g per minute per cm of catalytic aggregate. and in ills a mixture of propylene and water vapor; It is preferable that the space velocity be in the range of m 0 \ b 0 \ re Te and it is desirable that a, Y — not [o > 0. min/cm of catalytic ic mass 0 and a process is carried out Hydration at a pressure ranging from 0001 to Youve kilo JE ul 8. During this rate, it is desirable that the hydration process of ethylene be carried out at a pressure from 0000? to 00001 kilopascal; While the hydration process is carried out at a pressure from Y LI to vi A 0 Kpa 1, the effectiveness of the catalytic group was measured by monitoring the amount of alcohol; Unreacted ether and olefin over a period of one hour under standard test conditions (examples given below). The production of alcohol and ether was measured by gas chromatography (see Lad after); While the unreacted olefin is measured using a positive displacement wet type flowmeter. On it; It has now been found that by using the particular catalyst kit shown in this description it is possible not only to increase the time-equivalent yield (hereafter referred to as “5137”) and degree of responsiveness or method selectivity but the load to extend the life of the catalyst/support and thereby lower the frequency at which The catalyst / support on the device is changed or displaced This invention is explained by using the following examples:

- 11 1 Example Preparation of the catalyst “M!” 001 (g) in distilled water 70674 = X ( 12-tungstosilicic acid.xt, O dissolve .w/w) JAC g strength AA) phosphoric acid to which 0 water (1 #ml) orthophosphoric acid was added and then added slowly; stirring (pa) ,10) KHCO; In a separate bowl, melt the filling; The total volume is 0 to the acidic solution. And rinse the container three times with distilled water

KHCO; The washing products were added to the acidic solution (the amount of (Je 151 added -12) was chosen so that it gives one molar equivalent of potassium 2 per mole of acid per minute after stopping V0 dissolved in the solution). tungstosilicic d 2011. * 11 O Ve l) ¢ and it is a completely pure carrier of silica (7), Graces silica, then added silica. Coy escalated for an hour. ) silica pH and/or silica <) silica 1 hour at Visa de The catalyst was drained of the excess solution for one hour, dried in the air, and then weighed 1 liter of the final catalyst and it was 551 g; giving an acid load of 01 . g/l Vo and operation in the apparatus using recycled ethylene (unreacted) cool the gaseous product leaving the reactor to 0 ambient in a high-pressure cooler before passing to a high-pressure gas-liquid separator to separate the rich phases with water and rich in ethylene, and the passage of the water-rich phase

11- As well as the by-product of ethanol, which contains a predominant percentage of the ethanol product, through a control valve to a collection vessel at acetaldehyde and diethyl aldehyde acetate from the gas separator = liquid to the bottom of the ethylene ambient pressure Then the ethylene-rich stream (sana) ethanol passes through a water-washing tower where it meets a counter-stream of water that removes most of the ethanol (ethylene) from the gaseous stream flowing upwards. As for the purified gaseous stream; It is 0 mg/© ethylene + diethylether but contains in the region 90 mg/l diethyl ether per liter of gas (as ethanol and less than 0 + mg acetaldehyde per liter of acetaldehyde measured at normal temperatures and pressures, then passed to a recirculation machine for backcharging into the reactor.The water flow in the washing tower in the region was 170 ml/h and the level in the tower was maintained by means of the level set and the liquid intake adjusting valve; 0 The liquid coming out of the washing tower is mixed with the liquid product from the gas-liquid separation and the ethanol content of the device was contained in the above-mentioned conditions, by charging one liter of the catalyst (acid charging) 10 g/l) as it was present in an example into the reactor. After starting the device, enter the ethylene 160 rtA, set the ve conditions and the target conditions, and confirm . The pressure entering the reactor was 69860 kPa (100 m), and the degree of exit from the reactor was 1456 m (ep YO) and the degree of entry into the reactor was: g/h; The molar ratio of water was 19010 ethylene and the ethylene return flow rate was 000; The water flow rate in the washing tower was + FAY entering the ethylene reactor. m) 10-31 ml/hour at an ambient temperature of 17°C (preferably ©

We obtained the following performance in the pilot device by catalyst example 1; Yield (Jl) VAY, 0 “ethanol product time equivalent STY ; second Ji cher STY V,+ Y diethylether ; Acetaldehyde STY 2006 “Selectivity to ethanol 794.7 (selectivity is defined as the ratio of moles of ethylene carried into ethanol to total moles of m-ethylene converted into products). A non-identical comparative test of the invention is now shown; An experiment performed in a manner similar to Example 1; But in a device in which the unreacted ethylene cycle is not returned to the reactor. The data is produced in a device operating a reactor containing 500 ml of a catalyst similar to that mentioned in Example 1 under isothermal conditions measured 0 by coefficient 01 for comparison with the catalyst scale in Example 1 . The reactor inlet pressure was 4875 kPa 8, the reactor inlet temperature was 0.0 5', the ethylene flow rate was fan VE£ h, and the mole ratio of water: ethylene to the reactor was 0.700. And we have achieved the next Ni a p in the pilot device by means of this catalyst f | For comparative testing ¢ ethanol yield “ethanol 97; diethylether; 167 STY; STY V,Y acetaldehyde 00 ; selectivity; 771,76 (selectiveness has the same definition as above).

Claims (1)

Claims_ of protection 1 1 - A continuous process of hydration of olefins 5 with water in the vapor phase Y to the corresponding alcohol alcohol in the presence of a mixed acid salt as a catalyst r. This method includes recycling or passing the olefin Unreacted olefin to ¢ reaction (hydration saad) which is characterized by ob The salt of the mixed polyacid is mono-or di-potassium salt ea mono-or di-potassium salt silicotungstic acid 1 or phosphotungstic acid of which v is soluble in a polar solvent at less than 00 m. \"- a process as mentioned in claim 1; in which the catalyst does not have more than Y moles of an alkali metal cation “or two moles of ¥ an alkaline earth metal cation ¢ per mole of the mixed acid ¢ -Y 1 process as mentioned in claim 3 in which the catalyst supports the siliceous support Y . Catalyst 7 has a molar ratio of 1.1 — 1? and a gas hourly space velocity (GMSV) of ved ¢ to Yo + g/min/cm. — $ \ m lac —-0 \ As stated in claim ¥¢ Cus the catalyst concentration is from 5 to 7 Y w/w based on the total weight of the supported catalyst. Hydration is a process, as mentioned in claim 3, in which a hydration reaction takes place 5-1. to 90 °C 101 at a temperature of olefin olefin Y VY 1 is a process as mentioned in claim 0; the olefin includes ethylene Y, propylene, or a mixture thereof. 1 4- A process as mentioned in the claim “V” in which the olefin contains ethylene Y and the hydration reaction takes place at a temperature of Y 0 * 1 and x 5 . \ 4 - an operation as mentioned in the claim; In which the olefin includes propylene and the Jeli hydration reaction takes place at the temperature of La Ye. -6v ‎YYEY